For the United States to have a credible military deterrent, American forces must be ready to defend the US and its legitimate national interests. That is what makes the current controversy over American military readiness so important.
Enough previous questions have been raised about the adequacy of the American military's state of readiness to indicate that a nonpartisan look at the question is demanded. After the election the issue should be examined carefully to determine whether the military's readiness is sufficient - and, if it is not, to recommend steps that need taking.
Whether the state of readiness is better or worse than four years ago is not the point. The issue should be whether it is adequate to the national need. The proper readiness, of course, is a readiness to defend, not attack.
The current discussion ought to be seen in another perspective as well. Military strength is a favorite election-year topic of political parties and their candidates. In 1960 John F. Kennedy claimed that a missile gap existed between the US and the Soviet Union, a view he reversed upon assuming the presidency. Four years ago Ronald Reagan asserted that the American military's readiness to sustain combat was deficient: Supporters insist he has moved to redress that situation, although not all improvements have yet shown up in the field.
The latest accusation, that readiness is both inadequate and declining, came from the staff of the Democratic-controlled House Appropriations Subcommittee on Defense. It charged the Army has too few men and supplies ''to sustain combat operations in a major contingency,'' and that smaller nations' navies could so damage the US Navy as to cause ''a national disgrace.''
Denial of the committee's conclusions came promptly from Defense Secretary Caspar Weinberger, who called them ''not only wrong but dangerously wrong.''
It is important that the government not spend so much money buying expensive and much-debated new weapons systems that it must scrimp on funds demanded to keep the military ready to defend America - such as money for training and ammunition. The nation requires a clarity in its defense spending priorities. The effort to build an impressive military machine may be at the price of a more modest goal, of a properly equipped, manned, and trained regular military force.
Even that kind of military readiness is hardly the ultimate, anyway. More important is American readiness to negotiate, to move toward agreement. A more vital question than ''Are we ready to fight a war?'' is: ''Are we ready to secure a peace?''